The invention relates to a gas distributor for small-bubble aeration of water.
Gas distributors of this type are used in the aeration of water, for instance in biological waste water treatment plants, or for supplying oxygen to improve living conditions in lakes (artificial respiration).
In conventional gas distributors, it is assumed that each longitudinal and transverse side of the bottom plate has separate joints so that a total of four lateral joints is required per plate. In this case, problems may arise at the four junction points in the corners between the individual profiled sections, because the diaphragm at these points may tend to tear easily and therefore must be replaced. Furthermore, conventional gas distributors typically include L-shaped or angular members which are only designed or suitable for straight, and not for curved structures. Typically, a member is inserted into the space defined by the two assembled L-members and the diaphragm. In these distributors, the member can only be inserted from one of the two ends of the recess, because of which, the diaphragm may easily be touched and be possibly damaged.
Moreover, conventional gas distributors include suppressing elements, which are secured by means of screws that extend through the diaphragm and, as a result, may possibly damage it. The application of such elements in conventional gas distributors is not only time-consuming, but poses a danger of damaging the diaphragm. Such damage occurs gradually and is the result of the variable pressure conditions between the diaphragm and the base plate.
Thus, there is a need to provide a gas distributor which ensures that a sufficient air circulation space exits between the suppressing elements and base element so as to reduce the formation of bulges, and thus increase the efficiency of the device.
Further, in conventional gas distributors, strips and screws are used to secure the diaphragm to the base plate, in the course of which different materials, such as stainless steel and plastic, are screwed together. Under the effects of heat and cold, this can lead to tensions and tears due to varying expansion coefficients. Furthermore, clamping methods are used, although this type of fastening is associated with difficulties under varying pressure. With the methods of adhesion used, there is the danger that the diaphragm will be damaged while being pulled away. Finally, changing a foil is so labor-intensive with known methods that the process is no longer practical.